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arXiv · 1812.04765

Strong lensing constraints on modified gravity models

De-Chang Dai·Dejan Stojkovic·Glenn D. Starkman
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Abstract

We impose the first strong-lensing constraints on a wide class of modified gravity models where an extra field that modifies gravity also couples to photons (either directly or indirectly through a coupling with baryons) and thus modifies lensing. We use the nonsingular isothermal ellipsoid (NIE) profile as an effective potential, which produces flat galactic rotation curves. If a concrete modified gravity model gives a flat rotation curve, then the parameter $Γ$ that characterizes the lensing effect must take some definite value. We find that $Γ= 1.24\pm0.65$ at $1σ$, consistent with general relativity ($Γ= 1$). This constrains the parameter space in some recently proposed models.

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De-Chang Dai, Dejan Stojkovic, Glenn D. Starkman. 2018-12-12. Strong lensing constraints on modified gravity models. https://doi.org/10.1103/physrevd.98.124027

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